This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: Strengthen ICF hash
- From: Andi Kleen <andi at firstfloor dot org>
- To: Jan Hubicka <hubicka at ucw dot cz>
- Cc: gcc-patches at gcc dot gnu dot org, mliska at suse dot cz
- Date: Sun, 01 Mar 2015 18:11:00 -0800
- Subject: Re: Strengthen ICF hash
- Authentication-results: sourceware.org; auth=none
- References: <20150301214405 dot GB95914 at kam dot mff dot cuni dot cz>
Jan Hubicka <hubicka@ucw.cz> writes:
>
> The hash itself is quite simple (borrowing incremental hash for constants adding
> very simple match for other stuff + logic to skip things that may match even if
> they are syntactticaly different). The hash can be strenghtened significantly,
> but I suppose we may do it based on actual profiling. It also is loosely based
> on varasm.c constant pool hash implementation that was OK for years.
FWIW i have some older patches to use a stronger/faster spooky hash for
incremential hash. But I never submitted them because I wasn't able
to show clear gains for the type hashing (that was the original
motivator) since you fixed it.
But if you're interested I can update them to the latest tree.
spooky is very good at dealing with a lot of input data quickly.
-Andi
--
ak@linux.intel.com -- Speaking for myself only